give me an ai code in c# in csharp

Here's an example code for implementing a simple neural network in C#:

using System;

class NeuralNetwork
{
    static void Main()
    {
        // Input data
        double[][] input = new double[4][];
        input[0] = new double[] { 0, 0 };
        input[1] = new double[] { 0, 1 };
        input[2] = new double[] { 1, 0 };
        input[3] = new double[] { 1, 1 };

        // Output data
        double[][] output = new double[4][];
        output[0] = new double[] { 0 };
        output[1] = new double[] { 1 };
        output[2] = new double[] { 1 };
        output[3] = new double[] { 0 };

        // Create a neural network with 2 input nodes, 1 hidden node, and 1 output node
        NeuralNetwork nn = new NeuralNetwork(2, 1, 1);

        // Train the neural network using backpropagation
        nn.Train(input, output, 10000, 0.1);

        // Make a prediction
        double[] prediction = nn.Predict(new double[] { 0, 1 });
        Console.WriteLine("Prediction: {0}", prediction[0]);
        Console.ReadKey();
    }

    private double[][][] weights; // weights[i][j][k] = weight from neuron j in layer i to neuron k in layer i+1
    private double[][] neurons; // neurons[i][j] = output of neuron j in layer i
    private int[] layers; // layers[i] = number of neurons in layer i

    // Create a neural network with given number of layers and neurons in each layer
    public NeuralNetwork(params int[] layers)
    {
        // Initialize layers and neurons arrays
        this.layers = new int[layers.Length];
        for (int i = 0; i < layers.Length; i++)
        {
            this.layers[i] = layers[i];
        }

        neurons = new double[layers.Length][];
        for (int i = 0; i < layers.Length; i++)
        {
            neurons[i] = new double[layers[i]];
        }

        // Initialize weights array
        weights = new double[layers.Length - 1][][];
        for (int i = 1; i < layers.Length; i++)
        {
            weights[i - 1] = new double[layers[i]][];
            for (int j = 0; j < layers[i]; j++)
            {
                weights[i - 1][j] = new double[layers[i - 1]];
                for (int k = 0; k < layers[i - 1]; k++)
                {
                    weights[i - 1][j][k] = GaussianRandom();
                }
            }
        }
    }

    // Train the neural network using backpropagation
    public void Train(double[][] input, double[][] output, int iterations, double learningRate)
    {
        for (int iter = 0; iter < iterations; iter++)
        {
            for (int i = 0; i < input.Length; i++)
            {
                Predict(input[i]);

                // Backpropagation
                double[][] delta = new double[layers.Length][];
                for (int j = 0; j < layers.Length; j++)
                {
                    delta[j] = new double[layers[j]];
                }

                for (int j = 0; j < neurons[neurons.Length - 1].Length; j++)
                {
                    delta[neurons.Length - 1][j] = neurons[neurons.Length - 1][j] - output[i][j];
                    for (int k = 0; k < neurons[neurons.Length - 2].Length; k++)
                    {
                        weights[weights.Length - 1][j][k] -= learningRate * delta[neurons.Length - 1][j] * neurons[neurons.Length - 2][k];
                    }
                }

                for (int j = neurons.Length - 2; j >= 1; j--)
                {
                    for (int k = 0; k < neurons[j].Length; k++)
                    {
                        double sum = 0.0;
                        for (int l = 0; l < neurons[j + 1].Length; l++)
                        {
                            sum += weights[j][l][k] * delta[j + 1][l];
                        }
                        delta[j][k] = neurons[j][k] * (1.0 - neurons[j][k]) * sum;
                        for (int l = 0; l < neurons[j - 1].Length; l++)
                        {
                            weights[j - 1][k][l] -= learningRate * delta[j][k] * neurons[j - 1][l];
                        }
                    }
                }
            }
        }
    }

    // Make a prediction
    public double[] Predict(double[] input)
    {
        // Set input layer
        for (int i = 0; i < input.Length; i++)
        {
            neurons[0][i] = input[i];
        }

        // Feedforward
        for (int i = 1; i < layers.Length; i++)
        {
            for (int j = 0; j < neurons[i].Length; j++)
            {
                double sum = 0.0;
                for (int k = 0; k < neurons[i - 1].Length; k++)
                {
                    sum += weights[i - 1][j][k] * neurons[i - 1][k];
                }
                neurons[i][j] = Sigmoid(sum);
            }
        }

        // Return output layer
        return neurons[neurons.Length - 1];
    }

    // Sigmoid activation function
    private static double Sigmoid(double x)
    {
        return 1.0 / (1.0 + Math.Exp(-x));
    }

    // Gaussian random number generator
    private static Random random = new Random();
    private static double GaussianRandom()
    {
        double u1 = 1.0 - random.NextDouble();
        double u2 = 1.0 - random.NextDouble();
        double randStdNormal = Math.Sqrt(-2.0 * Math.Log(u1)) * Math.Sin(2.0 * Math.PI * u2);
        return randStdNormal;
    }
}
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This code trains a simple neural network to solve the XOR problem. The network has 2 input nodes, 1 hidden node, and 1 output node. The Train method uses backpropagation to adjust the weights in the network to minimize the error between the predicted output and the actual output. The Predict method takes an input and returns the output predicted by the network.

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